Remands in the micro-milling process machining market surge, and the competition focus of the industry has been developed toward intelligentization, wherein the most important section is real-time machining vibration monitoring and consideration, which may serve as main shaft running status understanding and device process yield control. However, currently, a commercially available machining vibration sensing apparatus with high precision has a relatively high unit price and unfavorable introduction feasibility.
A main function of on-line chatter avoidance is protecting a cutting machine tool. By means of a mini-sized vibration sensing element mounted in a machining area of the cutting machine tool (for example, on sheet metal of a main shaft), analysis software disposed on a rear end can detect a dynamic vibration frequency during single machining, but lacks of a cutting vibration mode information. If the dynamic vibration frequency and the vibration mode information of machining of the main shaft are both known, a status of the machining may be adjusted, and a rotation speed and feeding of the main shaft can be changed on line, so as to minimize waste of a workpiece material and also prevent a cutting tool from being damaged.
The U.S. Patent Publication No. US 20140067289A1 discloses an integrated vibration measurement and analysis system, which includes a vibration measurement signal processing method, an integration or differentiation vibration signal may be analyzed in real time by using a filter means of an IIR, so as to lower a complex degree of system hardware and a data storage demand.
However, the foregoing patent document does not disclose a method to directly eliminate an ambient noise and quickly obtain dynamic vibration frequency and mode information during machining.
In view of this, therefore, it is necessary to provide a method for acquiring a dynamic vibration frequency and a vibration mode on line to resolve the foregoing problems.